The invention relates to metal detectors, and specifically to electronic circuits for metal detectors. Metal detectors commonly include an oscillator (or transmit) coil and two detector (or receive) coils. The detector coils are typically positioned on either side of the oscillator coil and substantially equidistant therefrom. The oscillator coil is provided with an oscillatory signal that is inductively coupled to the detector coils. Metal passing through the coils causes an imbalance in the inductively coupled signals, which can be used to detect the presence of metal.
Vibration of the metal detector can result in the metal detector falsely determining that there is metal in the metal detector. To compensate for the false determinations of metal due to vibration, the sensitivity of the metal detector can be reduced. Reducing sensitivity, however, can result in some metal in the metal detector not being detected properly.